Optical instrument



June 9, 1942. E, KRIMSKY 2,285,987

OPTICAL INS TRUMENT Filed Maroh'25, 1940 2 Sheets-Sheet l June 9, 1942. E. KllMs'KY l 2,285,987

OPTICAL INSTRUMENT v Filed March 25, 1940 'fsheets-sneet 2 Patented June 9, 1942 UNITED STATES PATENT OFFICE OPTICAL INSTRUMENT Emanuel Krimsky, Brooklyn, N. Y.

Application March 25, 1940, Serial No. 325,875

7 Claims.

My invention relates to a light weight slit-lamp and an associated optical instrument and has particular reference to a slit-lamp and microscope unit adapted for use in examinations of the surface and sub-surface of the eyeball.

A typical slit-lamp and microscope unit is disclosed in Patent No. 1,631,329, patented June 7, 1927, by W. L. Patterson. Instruments of this type having self-contained batteries are expensive, bulky and cumbersome. Furthermore, such instruments require the use of both hands of an operator for their operation. The physician is therefore not aorded the free use of his hands to manipulate the object under examination. Moreover, where the slit-lamp microscope of the above referred to type may be detached and replaced by other instruments, it will be found that such an interchange delays the examination and is disconcerting to the patient.

The main object of my invention isv to provide an extremely light weight, compact slitlamp and microscope device that is economical to manufacture and simple to operate.

Another object of my invention is to provide an instrument of the class described which may be manipulated by one hand of the operator so as to permit manipulation of another instrument with the other hand of the operator.

Another object of my invention is to provide a slit-lamp and microscope adapted to be attached to an eye-glass frame to afford complete freedom of the operators hands for manipulations incidental to the various examinations, or necessary operations.

A further object of my invention is to provide a novel means to vary the form of a light beam in a slit-lamp.

For a full disclosure of the invention, reference is made to the accompanyingy drawings, wherein- Figure 1 is a plan view of a hand-supported type of slit-lamp and miscroscope embodying my invention;

Fig. 2 is a view in section on line 2.-2 of Fig. 1;

Fig. 3 is a side view of the device;

Fig. 4 shows a modification of the slit-lamp and microscope associated with an eyeglass frame;

Fig. 5 is a view in section on line 5-5 of Fig. 4;

Fig.` 6 is a view in section on line 6-6 of Fig. 4;

Fig. 7 is a view in side elevation of the novel slit-lamp associated with the device;

Fig. 8 is a view in section on line 8-8 of Fig. 7;

Fig. 9 is an end view of the slit-lamp;

Fig. 10 is a schematic diagram showing various shapes of light beams projected by the slitlamp; and

Fig. 11 is an exploded view showing the structural elements of the slit-lamp.

Referring to the drawings in detail, the slitlamp miscroscope in one embodiment comprises an elongated bar I which is provided with a linger hold 2 in the form of a circular opening 3 extending transversely through one end of the bar. The bar I is cylindrically enlarged near its center and is provided at that point with a circular opening 4 extending therethrough at a right angle to the opening 3. The opening 4 is constricted at one end to form a shoulder 5 and is provided with internal threads 6 at the opposite end. The lens system is a high power short focus type such as a ten power (10X) double aplanatic lens system or a pair of planoconv-ex lenses 'I and 8 as are mounted in the opening 4. The lens I rests on shoulder 5 and is separated from the lens 8 by a circular collar 9. The lenses are secured in position by an externally threaded ring I0. The bar I is provided with circular channel II adjacent the hole 4. The channel extends through the bar at an angle of forty-five degrees with respect to the optical axis of the lens system. The channel II is adapted to receive a slit-lamp l2.` The lamp unit is secured in position by a set screw I3.

In another embodiment of my invention, the slit-lamp and microscope is adapted to be removably mounted on the lens or frame of an operators eyeglasses as is shown generally in Fig. 4 of the drawings. In this form, the microscope comprises a circular plate I4 which is provided with centrally located circular opening I5. The plate I4 may be detachably -secured to the eyeglasses by means of supports IB, I'I and I8 which are attached to the side of the plate` facing the lens of the eyeglass. Supports I6 and I'l are L-shaped members Which are secured by screws I9 and 20 to the lower portion of plate I4, as shown in Fig, 4. The supports I6 and I1 are bent at their outer ends to form channels 2| and 22 which receive the edge of the eyeglass 23. As an equivalent or more simple construction, the supports I6 and I'I may be formed integrally with the plate I4. The support I8 is pivotally mounted in a yoke 24 formed in the end of a vertical member 25 which. is` secured to the face of plate I4. The lower end of member 25 has a bent out portion 26 which. is perforated to receive one end of a spring 21, the other end of which is attached to the support I8. The tension of spring 21 draws the support I8 downwardly about its pivot causing it to engage the edge of the eyeglass frame 23. The support I8 is extended at one end beyond its pivotal point to serve as a lever by which the operator may raise the frame engaging end of the support and attach the plate I4 to the eyeglass. The frame engaging end of support I8 is bent to form a channel 28 which engages the upper edge of the eyeglass frame. The microscope comprises a cylindrical tube 219 which is constricted at its outer end to form a shoulder 30 and is interiorly threaded` at the opposite end. A lens 3| is positioned i'n the tube 29. Lens 3| rests on the shoulder 39 and is secured in the tube by an externally threaded ring 34. The cylindrical tube 29 is formed integrally with an arcuate bar 35 which is curved horizontally and outwardly away from the plane of plate III4 and the operators eyeglasses. The outer end of bar 35 is provided with a channel 36 which is adapted to receive a slit-lamp 31. The slit-lamp is secured in place by a set screw 38. The curvature of bar 35 Vis such that the slit-lamp 31 is supported in the channel 38 at an angle of about thirty degrees with respect to the optical axis of the microscope to direct the light ori the focal point of the lens system. The plate I4 may be secured to bar 35 by screws 35 The novel slit-lamp employed with the abovedescribed microscopesA comprises a slit-lamp holder and a lensl tube to concentrate and focus the light; from the lamp. The slit-lamp holder comprises a metal tube 39 which has anenlarged knurled head 49. The headv 40 is flattenedat one point 4I for a purpose to-b'e described. The opposite end of the tube 39 is internally threaded to receive' a slit-lamp 42. The Wall of. tube 39: is provided with a helical. slot 43. TheY metal. tube 3'9 is constricted adjacent the threaded portion thereof to form a shoulder 44'. Agcylindric'al tube 45 of insulating material having a closed end rests against. the shoulder 44. The insulating tube 45 contains` a metal cylinder 46 which is provided at one-end? with a slot 41. The closedend of the insulating tu'be 45 is perforated` at its center to receive acontaet pin 413-.V The contact pirr 45 is forced outwardly by a spring 4'9 which rests against the metal cylinder 46'. The. conductor comprising leads 551 and i3 suppliescurrent tothe lamp from a pocket battery' or other source'. The s101341 in cylinder 46'- receives lead 59:' which is securedtherein by crimping the slotted-end of the cylinder. Lead 5I engages the fiatv portion 4-I. A knurled tube 5-2 formsV a cap for the end-L Ill of the tube 39. therebycrimping lead 5I- against the portion 4I'. The cap 52 may besecured' in position with a set screw 53; A lens 54 issupported inthe enlarged end offa, tube* 55'. The lens tube 55 is provided with longitudinal slots-561. 4A cylindrical tube 521 receivesV the lens tube 551' and'- is adapted, toslip over theslit-lamlp 42 andthe tube 390i the-lamp holder. rEhe wall ofthe tube 51 is providedT with a threadedl pin 58 which engages the helical slot'43 in the Wall of the'l tube 39. The slit-lamp 42 contains alla-t looptype of filament 59 which produces a linear source of lightf To operate the slit-lamp, the condenserv lens 54 is brought into the desiredfocus by' sliding the lens tube 55 in the cylinder 51'. The cap- 52k and tube 39'- of they slit-lamp holder may thenl be rotated and caused tomove backward or forward in the cylinder 51 through the cooperation of the pin 58 and the helical slot 43. When the slitlamp is out of the focal plane of and closer to the condenser lens 54, a circle of light 60 is projected. However, when the longitudinal movement of the slit-lamp holder brings the lamp filament 59 within the focal plane of the lens 54, a vertical slit 6I or a horizontal slit 62 of light is projected depending upon whether the line filament is vertical or horizontal when in focus.

To attach the slit-lamp to the microscopes described herein, the condenser lens tube 55 is removed from the cylinder 51. The slit-lamp holder may then be inserted in either the channel II of the microscope shown in Fig. l or the channel- 36 of the microscope shown in Fig. 4. The slit-lamp may be secured in either channel by means ot the set screws` provided. The set screws in each instance grip the metal cylinder 51 of the slit-lamp holder and do not interfere with the backward and' forward movement of the slit-lamp 42T. The condenser lens. tubeA 55l may then be inserted in the cylinder 51 and moved longitudinallyY therein untilv the' lens 54" is` brought to focus on the focal point of. the lens systems of the microscopes.. As above described,v the slit-lamp holder. may be moved backward. o'r forward by rotating the cap 52 to selectively obtain a vertical slity a horizontal. slit or a homogeneous circle of light as' may be desired..

The microscope shown in Figs.V 1 to 3 having the slit-lampA incorporated therein areV extremely light, weighing approximately ank ounce. The

physician in using the microscope may adjust the slit-lamp to. satisfy his particular requirement and holdthe instrument by the finger supports 24 with the thumb and forefirig-er of one'handV thus leaving one hand free to manipulate the object examined.

AvIn the embodiment of my invention shown in Figs. 4 t`o16- in` which thel microscope i-s attached to the' eyeglass-frame', the physician isffree to use both hands during the-examination. This type of instrumentusuaily contains alower power lens system t`oprovide a l'on'ger foca-llength, thereby giving increased room to manipulate the object exlazrilined.A

Whilel have disclosed a preferred form: of the invention, itis toA be understood that other modi- 'cationsand various equivalents are contemplated such as maybe embraced within the-scope of thel appended claims.

l. In combination, a frameA member having an opening extending transversely therethrough, a microscopelen-sposition'ed in saidopening, said member being provided with a second opening 'extending' transversely therethrough, theV axes of said openings` being directed to form an" angle therebetween, said second opening being adapted tol detachz'ifb'ly`l support alamp unit therein whereby the light from' theA lampmay be projected on an object positioned to one side of the' frame mernber and means mounted onn theI other side of the frame member for securing the member toan eye glass, saidmeanscomprising a cla'mp element rigidly xed' tothe member an'd another clamp element pivotally secured' to the member, said clamp elements being operative to engage opposite sides' of theF eyeglass.

2. In a device as set forth in claim 1, wherein the fra-me member comprises anY end portionbent out of the plane of the member, the secondL operi- Ving through which the light support extends being formed in the bent end portion 3. A device as set forth in claim 1, wherein the lamp unit comprises a tubular element, a condensing lens mounted therein, an electric lamp supporting element slidably mounted in said tubular element to permit movement toward and away from said condensing lens, means for moving said lamp supporting element comprising a pin on one of said elements, a helical slot formed in the wall of the other element, said pin being engaged in said slot whereby rotation of one element with respect to the other element will cause the lamp supporting element to slide along said tubular element.

4. A device as set forth in claim 1 wherein the light support comprises a tubular member, a condensing lens mounted on said member, a lamp supporting member slidably mounted on the tubular member, an electric filament lamp carried by the supporting member, said lamp and supporting member being adjustable to vary the position of the filament with respect to the focal point of the lens, interengaging means associated partly with said tubular member and partly with said supporting member and being operable upon rotation of one of said members to vary the position of the lament and lamp with respect to the focal point of the lens for varying the cross-sectional shape of the light beam from the lamp.

5. A device as set forth in claim 1 wherein the light support comprises a tubular member, a condensing lens mounted on said tubular member, an electric filament lamp and a supporting member therefor slidably mounted on said tubular member to permit movement toward and away from said lens to vary the position of the lamp filament with respect to the focal point of -said lens, means for moving said lamp and supporting member comprising a pin on one of said members, a helical slot formed in the wall of the other member, said pin engaging said slot whereby rotation of one member with respect to the other member will cause the lamp and supporting member to slide along said tubular member whereby to cause the rays of light from said filament to be varied selectively to form a fiat beam of light positioned in one plane, a flat beam of light in a plane normal to said rstnamed plane, or a homogeneous circle of light.

6. In a device as set forth in claim 1, wherein each clamp element is provided on the free end with a recessed portion for engaging the edge of' the eyeglass, and a spring member operably secured to the pivoted clamp element for forcing the latter against the eyeglass.

7. In a device as set forth in claim 1, wherein the frame member is shaped to provide a circular enlarged portion concentric with the rst-named opening, the clamp elements being secured adjacent the outer edge of said enlarged portion.

EMANUEL KRIIWSKY. 

